Subscribe to our free daily newsletters
  Energy News  

Subscribe to our free daily newsletters

DNA Technique Aids Crops And Trees At Risk From Deadly Honey Fungus

Controlling the fungus is very difficult. The most effective pesticide to prevent Armillaria root disease, methyl bromide, is being phased out (except for quarantine and critical uses) due to its role in depleting the stratospheric ozone layer. There are few alternatives for preventing or curing infections.
by Staff Writers
Bristol, UK (SPX) Nov 30, 2010
An international team of scientists has developed a new technique to aid crops at risk from a devastating agricultural parasite commonly known as the 'honey fungus', one of the most serious diseases of trees and shrubs across the northern hemisphere. The development allows crop to be screened for natural resistance by adding DNA with fluorescent genes to the fungus before being planted out.

The research, a collaboration between the United States Department of Agriculture's Agricultural Research Service and the University of Bristol, has the ability to transform and to genetically manipulate the plant-pathogenic fungus Armillaria mellea by artificially introducing DNA into it. DNA was introduced using Agrobacterium, a bacterium that is commonly used to genetically modify plants.

This powerful technique has been immensely important in the study of other pathogens in the laboratory, in terms of pinpointing how the pathogens enter and spread through plants and, then, developing control practices that prevent or minimise infection.

The honey fungus is a devastating disease for many hundreds of different species of trees and shrubs, ranging from those important for timber production, various orchard and vine fruits and numerous ornamental shrubs, so is of importance in forestry, agriculture and gardening.

Infections result in a reduced growth rate of the host plant, premature wilting of the foliage, lower harvests and eventually death of the plant. This is often accompanied by the growth of honey-coloured toadstools - the fruiting bodies of the fungus, which are responsible for its common name.

The fungus attacks the roots of the plant and can spread through the soil, meaning that once infections are established they can move to nearby plants and spread throughout a wide area. Indeed the term "humungous fungus" has been coined for this group of Armillaria species as some colonies have been found where one individual fungus covers an area in excess of 15 hectares.

Controlling the fungus is very difficult. The most effective pesticide to prevent Armillaria root disease, methyl bromide, is being phased out (except for quarantine and critical uses) due to its role in depleting the stratospheric ozone layer. There are few alternatives for preventing or curing infections.

The disease is particularly damaging to orchard or vine crops as the infection could wipe out production long before the costs of establishing the orchard have been recouped. Because the fungus persists on dead roots buried in the soil, it is likely that any new plants put into the same area would also be vulnerable to attack.

In a garden setting there are no chemical control measures, meaning that using naturally resistant plant varieties is important. This work will allow us to genetically modify the fungus so that it can be easily identified, measured and studied in a lab situation.

Professor Gary Foster, a plant pathologist from the University of Bristol's School of Biological Sciences, said: "The ability to track and visualise the fungus as it enters and grows through a plant will help us understand how this fungus behaves in the field. Such knowledge is an important step towards helping us to devise better control strategies in the future."

Dr Kendra Baumgartner, a specialist in vine and tree crop diseases from the U.S. Department of Agriculture, said: "Efforts are already under way to identify rootstocks of grapes, walnuts, and stone fruits that are naturally resistant to infection. The improved screening that is enabled by using transformed strains of Armillaria should allow more rapid identification of resistant plant materials."

Being able to transform the fungus also helps with investigations into its population structure. These species are unusual as they can produce new genetic types without going through a conventional sexual cycle. When two individuals meet, there is the chance that nuclei from one strain can invade and recombine with nuclei in the other fungus, giving rise to new genotypes with new and novel traits.

Dr Andy Bailey, a mycologist at the University of Bristol, said: "This can be studied in far more detail now that we are able to introduce genes that are easy to follow."

The work was funded with support from the Organisation for Economic Cooperation and Development's Cooperative Research Program in Biological Resource Management for Sustainable Agricultural Systems, and will appear in the December issue (24) of Applied and Environmental Microbiology.

Share This Article With Planet Earth DiggDigg RedditReddit
YahooMyWebYahooMyWeb GoogleGoogle FacebookFacebook

Related Links
University of Bristol
Farming Today - Suppliers and Technology

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

Soil Microbes Define Dangerous Rates Of Climate Change
Exeter, UK (SPX) Nov 30, 2010
The rate of global warming could lead to a rapid release of carbon from peatlands that would further accelerate global warming. Two recent studies published by the Mathematics Research Institute at the University of Exeter highlight the risk that this 'compost bomb' instability could pose, and calculate the conditions under which it could occur. The same Exeter team is now exploring ... read more

ESA Attending UN Climate Conference

Two New Earth Observation Missions Chosen For Further Study

Express Map Delivery From Space

GOES-13 Looks At Thanksgiving Travel Conditions

Space Ministers Emphasise Priority To Deliver Galileo And GMES

New Simulator Offers Ability To Record And Replay GLONASS And GPS

Russia To Launch New Generation Satellite In 2013

SkyTraq Introduces New GLONASS/GPS Receiver

Managing wood to carve a strong community

Mexico Forest Communities Excel In Capturing Carbon

Developing Countries Often Outsource Deforestation

Indonesia's billion-dollar forest deal in danger: Greenpeace

Biofuels Have Consequences On Water Quality And Quantity In Mississippi

Verenium Announces Collaboration With Edible Oil Leader Desmet Ballestra

Lufthansa First Airline To Use Biofuel On Commercial Flights

Brazil Invests In Scania Ethanol Buses

Solis Partners Awarded Solar Contract For New Vertical Screen HQ

Funding To Help Solve Solar Energy Puzzle

Fast Food Goes Green

Konarka's Power Plastic Achieves World Record NREL Efficiency Certification

Vestas Selects Broadwind Towers For Glacier Hills Wind Project

Optimizing Large Wind Farms

Enhancing The Efficiency Of Wind Turbines

GL Garrad Hassan Chosen For SMart Wind's 'Hornsea' Zone

China mine flood traps at least seven: state media

29 still trapped in New Zealand coal mine

All 29 trapped in China mine rescued

Mob violence leaves nine dead at China mine

Chinese micro-blog re-emerges after shutdown

Empty chair for Liu at Nobel ceremony: activist

China harassing Mongols ahead of dissident release: activist

China overturns 10 percent of death sentences

The content herein, unless otherwise known to be public domain, are Copyright 1995-2010 - SpaceDaily. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement